In silicoassembly and nanomechanical characterization of carbon nanotube buckypaper

Abstract

Carbon nanotube sheets or films, also known as "buckypaper", have been proposed for use in actuating, structural and filtration systems, based in part on their unique and robust mechanical properties. Computational modelling of such a fibrous nanostructure is hindered by both the random arrangement of the constituent elements, as well as the time and length scales accessible to atomisticlevel molecular dynamics modelling. Here we present a novel in silico assembly procedure based on a coarse-grain model of carbon nanotubes, used here to attain a representative mesoscopic buckypaper model that circumvents a need for probabilistic approaches. By variation in assembly parameters, including the initial nanotube density and ratio of nanotube type (single-and double-walled), the porosity of the resulting buckypaper can be varied threefold, from approximately 0.3 to 0.9. Further, through simulation of nanoindentation, the Young's modulus is shown to be tunable through manipulation of nanotube type and density over a range of approximately 0.2 to 3.1 GPa, in good agreement with experimental findings of the modulus of assembled carbon nanotube films. In addition to carbon nanotubes, the coarse-grain model and assembly process can be adapted for other fibrous nanostructures such as electrospun polymeric composites, high performance nonwoven ballistic materials, or fibrous protein aggregates, facilitating the development and characterization of novel nanomaterials and composites as well as the analysis of biological materials such as protein fiber films and bulk structures.

Self-folding and aggregation of amyloid nanofibrils

“…To attain large multi-fibril systems, amyloid plaques are assembled in silico via a modified procedure developed for nanotube assembly akin to an approach described in a previous study 41 , wherein twelve sequential layers of 20 fibrils (240 fibrils total) are deposited on a substrate and equilibrated (see Fig. 4A; the same procedure was used to arrive at the plaque depicted in Fig.…”

“…We apply computational nanoindentation to characterize the contact stiffness of the assembled plaques (as described above following a similar approach as outlined in a previous study 41 ). The indentation process itself is simple, where an indenter tip is pressed into the material and the forcedisplacement relationship is recorded (Fig.…”

Humic acid removal from water using a novel fabricated antifouling carbon nanotube bucky - paper membrane and effect of operating parameters

“…The porosity of BP membrane is primarily affected by CNTs type, length, CNT loading, preparation condition and sonication time (Li and Kröger, 2012;Yang et al, 2013). Different range of porosity from 30% to 90% have been reported based on different experiments (Cranford and Buehler, 2010). For example, it was reported that CNTs with higher length built higher porosity (Li and Kröger, 2012) and lower loaded CNTs developed lower porosity (Li and Kröger, 2012).…”

Solvent-free functionalization of carbon nanotube buckypaper with amines

“…Buckypapers, which are films (or mats) consisting of randomly entangled and densely packed carbon nanotube (CNT) networks, are a subject of the worldwide research effort as advanced materials for multiple and versatile applications including thermal and electrical conductive materials, catalysts, filtration membranes, sensors, actuators, fire retardants, among others (see [1][2][3][4] and references therein). It was demonstrated that buckypaper properties are influenced by changing the conditions employed during its assembly, in particular, the type of dispersant [5].…”